The Bruins recalled right wing Seth Griffith and returned forwards Alexander Khokhlachev and Jordan Caron to Providence Tuesday.

Griffith, who is tied for the team lead with five goals this season, was a victim of the waiver process and roster limit Monday, as the B’s had to demote him to stay at the 23-man roster limit with Brad Marchand coming off injured reserve.

The Bruins recalled Khokhlachev last week and brought up Caron on Sunday. Khokhlachev played in Boston’s last three games and scored the shootout winner in Friday’s victory over the Blue Jackets, but he was given just 2:53 of ice time in Monday’s overtime loss to the Penguins. Caron played only 3:35 on Monday.

The Bruins don’t play again until Friday. That gives them time to either determine the health of ailing players (David Krejci and Chris Kelly have both missed multiple consecutive games) or make more callups and demotions.

When you’re struggling to score as a team and half of your weapons are either sitting up on the ninth floor watching the game or playing elsewhere, it’s understandable to see why Bruins head coach Claude Julien is frustrated.

But, when you have the sense that you have to score twice for every goal that counts, that’s something altogether different. That’s what Julien felt after Monday’s 3-2 overtime loss to the Penguins, when goals in regulation by Patrice Bergeron and Carl Soderberg were disallowed.

If either goal counts, the Bruins skate away with a regulation win and two points.

“Again, you gotta score two goals every night to get one, it’s tough to win hockey games,” Julien lamented afterward. “We got some tough calls against us and our guys played hard right ‘til the end. Unfortunately, we didn’t get that second point that I thought we deserved.”

In the first period, it appeared Bergeron tapped a puck out of midair and put it behind Marc-Andre Fleury to tie the game, at one. But, referee Kyle Rehman — closest to the play — called it a good goal but after review, he was overruled by the three other officials on the ice, who said the puck was above the crossbar when Bergeron tapped it into the goal.

“On that first goal, the closest referee calls it a goal,” said Julien. “And then it’s no goal because the three furthest ones think it’s a high stick, so I guess that’s what’s frustrating in my mind. I don’t know what the league looked at. When I looked at the replay myself it looked more inconclusive. Now, they may contradict me and say they had a better angle from where they were, but that’s how it looked to me.

For Milan Lucic, it’s the small steps forward that are a sign that things are getting better.

On a line with Carl Soderberg and Loui Eriksson, the Bruins forward charged the net and was rewarded with a pass from Eriksson that gave him a chance to put the puck into a vacated net for just his fourth goal of the season. Lucic had all the time in the world to think about how many missed chances he’s had to score this season. Instead, he put it in for arguably the easiest non-empty goal he’s ever scored.

“I saw that he saw me and I knew he’s capable of making the play,” Lucic said of Eriksson. “It was just a great play by Loui, heads up play to see me there all by myself in front of the net and for myself you saw it was a little bit of delayed I just wanted to make sure I put that one in the back of the net.”

Lucic scored just his fourth goal of the season in Boston’s 3-2 overtime loss to the Penguins Monday night at TD Garden.

“I think, all in all, we played a pretty good game,” Lucic said. “We didn’t spend too much time in our own zone and we were able to create a bunch of scoring chances. I think what got a better is we were attacking with a lot more speed off the rush and we were strong on the pucks and driving to the front of the net and trying to create chances that way. For myself just on that goal, just driving the net, stopping in front, and a great play by Carl and Loui to get me the puck there for that first goal.”

He was also in front of the net when Eriksson put a puck on net with he and Soderberg charging the crease. The puck went in off Soderberg, but the goal was disallowed when the referee ruled on replay that Soderberg shoved it in with his glove.

David Pastrnak wasn’t about to complain about ice time or being mixed and matched with different lines. The 18-year-old was just happy to be making his NHL debut Monday night against Sidney Crosby and the Penguins.

The Czech played 10 shifts for a total of seven minutes, 53 seconds, with three missed shots, a hit, a takeaway and a giveaway in Boston’s 3-2 overtime loss to Pittsburgh.

The soft-spoken first-round pick reminded many of David Krejci afterward, speaking softly but admitting that he was indeed a little nervous getting the call up.

“A little bit for sure, but I said I just tried to play for the team and tried to do my best for the win and play my game,” Pastrnak said. “I think we played hard. We battled hard and tried to go to the net but it wasn’t enough. I tried to my best for the team and enjoy the time and enjoy the game.”

Coach Claude Julien mixed and matched Pastrnak on different lines Monday, taking advantage of the very fluid situation caused by the numerous injuries and limiting Brad Marchand, who was playing his first game back since coming off the injured reserve list.

In a perfect world, Milan Lucic would play with a healthy David Krejci and the two would anchor Boston’s top offensive line. With Krejci still battling through lower-body issues that have dogged him all season, that can’t happen and Boston’s best bet is skating Lucic on Carl Soderberg’s line and bumping that up to being the team’s second line.

On Monday, that line was very effective for Boston. Matched up against Evgeni Malkin’s line, the Lucic-Soderberg-Eriksson trio created numerous scoring chances, one of which led to a Lucic goal that started with Soderberg sending a spin-o-rama pass behind his back to Eriksson down low.

Malkin would strike on a second-period power-play goal, however, and would then provide the overtime dagger against Patrice Bergeron‘s line in Pittsburgh’s 3-2 overtime win.

Soderberg appeared to have a goal later in the second period when a rebound of a Lucic tip went off him and into the net, but it was ruled no goal after officials concluded that Soderberg had knocked the puck in with his hand.

Here are four other things we learned Monday:

BRUINS’ AIM FOR NET-FRONT PRESENCE DOESN’T WORK FOR OFFICIALS

The Bruins had trouble getting to the net Saturday against the Canadiens. They had trouble getting away with being in front of the net Monday.

A Patrice Bergeron goal was disallowed in the first period after it was determined that he knocked a rebound from Marc-Andre Fleury into the net with a high stick. The rule on the ice was a goal, but the other three officials ruled it no goal, with the replay confirming that Bergeron’s stick was above the cross bar.

That worst of it came later in the period, when Reilly Smith was the victim of a goaltender interference call. With Dougie Hamilton taking a shot from the point, Smith went to the net and was shoved into Fleury at the top of the crease. It was a tough break for Smith, who couldn’t get out of the way.